Eng-Tips is the largest engineering community on the Internet

Intelligent Work Forums for Engineering Professionals

Search results for query: *

  1. theoldwizard1

    Can I Extend Car Battery Charger Output Cable

    Here is a better chart. For a 3% voltage drop at 10A and a total (round trip) distance of 63' (close to 2 x 10m) you need 6 gauge wire. For a 20A load it jumps to 2 gauge. 12v voltage drop charts
  2. theoldwizard1

    Can I Extend Car Battery Charger Output Cable

    I agree with MikeHalloran "If it's for charging the battery of a fueled car, you still need moderately large cable, unless the charger has remote sense terminals." I don't have access to any wire gauge voltage drop charts but think 6 gauge or larger for a distance of 10 meters ! I worked for...
  3. theoldwizard1

    dual-clutch transmissions

    Ford is using it in the 2011MY US Fiesta and the 2012MY US Focus strictly because of its superior fuel economy compared to a conventional automatic transmission. Remember, "paddle shifter" are not required for this transmission, but sure would be fun !
  4. theoldwizard1

    dual-clutch transmissions

    When near infinite money is available, different solutions are available. Ford, and the rest of the high volume manufacturers, simply could not build an affordable car with wet multi-plate clutches. I'll bet that vehicle is RWD, not FWD, like most of the "real world" DCTs. I'll also bet it as...
  5. theoldwizard1

    Need education in gears

    Gear design is part science and part art. Factors like speed, torque and noise can not be ignored. Some "good" designs can not be built in volume due to cost issues. Don't forget, if you are using helical gears and applying a "significant" amount of torque, the gears will want to force...
  6. theoldwizard1

    How could that happen? Bad driveshaft!

    True story. Back in the 70s, a major auto manufacture was doing durability testing on a closed track. After about 10k miles the alternator bracket broke. It was replaced but failed again after another 10-15k. When the third one broke, the car was pulled off the test schedule until "root...
  7. theoldwizard1

    Clutch-type LSD setup

    There are many different implementation of LSD/locking rear axles. Some with clutches, so without. Your question can not be accurately answered without know exactly which design you are referring to.
  8. theoldwizard1

    dual-clutch transmissions

    Early prototypes could produce clouds of clutch smoke when doing a hold on a steep hill in about 30 seconds !
  9. theoldwizard1

    dual-clutch transmissions

    Believe it or not, I actually worked on the first prototype of Ford's DCT back in the mid 1980s ! Obviously it took awhile to get all of the bugs out and make it cost effective !! A lot of the questions you are asking have a lot to do with the "application". Are we talking a production...
  10. theoldwizard1

    Engine re-building for high rpm

    Very general ideas. High speed requires a very light rotating mass. You actually want to use thinner bearing surfaces (less friction). Do not overlook the windage tray/oil "scraper" (Mercury outboards picked up about 10 hp by redesigning their scraper and a few offer things on their new 4...
  11. theoldwizard1

    VR Crank Sensor Question

    mw5002 - Good reference link ! Hall effect seems to have fallen out of favor. My guess is that VR is cheaper even with the zero crossing circuit. Biggest problem with VR sensors seems to be epoxy "creep". Expansion and contraction of the sealing epoxy breaks the fine wires. I have seen it...
  12. theoldwizard1

    Alternator deisgn equations

    This is just for personal "background knowledge". I never had any "power generation" classes in my curriculum. In an alternator (or is the preferred term AC generator), what are the relationships between shaft speed, voltage, current, frequency and "number of turns of wire" ? Obviously wire...
  13. theoldwizard1

    12VDC Power Conditioning

    Go to a car audio store and buy a large capacitor.
  14. theoldwizard1

    Designing sliding spline to minimize torque lock up

    ATV, I'm curious. What did your static testing show ? Were there any original design specs/assumptions ? Do you have any "real world" data showing the actual torque applied to the shaft ? (It could be much higher than expected if the vehicle drive wheel is on rough terrain.) Those splines...
  15. theoldwizard1

    TCI (or CDI) IGNITION TRIGGERING PULSE TOLERANCE

    I disagree with what jbkettler has stated. "The analog (sine wave) signal goes into the control module and is viewed and digitized by an a/d convertor ,,," On all of the ECM/electronic ignition system I have worked on, the VR signal is "squared up" by a zero crossing detector circuit and a...
  16. theoldwizard1

    VR Crank Sensor Question

    VR sensors do not have "polarity". Their output signal looks like a sine wave and aligns with the "tooth" of the trigger wheel at the point where the voltage crosses from positive to negative. There is usually a "zero crossing" circuit in the PCM that detects this and then generates a square...
  17. theoldwizard1

    Conformal coating needed for BCMs?

    I concur with Mike "They're doomed". With surface mounted devices and lower (3V) uP operating voltages, experience tell me the ravages of time and moisture will kill you. Years ago, when ECM where very new technology, the company I worked for, switched from a split pin and socket connector to...
Back
Top